Ventilated rubber shoe



Oct. 30, 1962 RYOJI OKUYAMA 3,060,599

VENTILATED RUBBER SHOE Filed Oct. 14, 1960 2 Sheets-Sheet 1 mmvrox RYOJIOKUYAMA VWJ 7% 1%,

AT ORNEY United States Patent 6) 3,060,599 VENTILATED RUBBER SHOE RyojiOlruyama, 177 Takata Wadayamacho, Asakogun, Hyogoken, Japan Filed Oct.14, 1960, Ser. No. 62,723 1 Claim. (Cl. 36-3) This invention relates toa new rubber shoe and has as its primary object to provide a rubber shoewhich will be comfortable at all times, that is, during both hot andcold weather. To this end the invention utilizes the pressure of thefoot in walking to force fresh air into the shoe to replace the airtherein thus keeping it pure by driving out the stale air and itscontained moisture. The shoe therefore feels cool in summer and warm inwinter for the close moist air which would otherwise be presentcontributes both to the sensation of uncomfortable warmth in summer andthe chillness in winter.

To the attainment of these and other objects and ends, the inventioncontemplates the provision of an air chamber in the sole of the shoeinto which air is drawn from the atmosphere and from which air i forcedinto the interior of the shoe as the wearer alternately lifts his footand lowers it in walking. Preferably, the air chamber is filled withsponge rubber or equivalent resilient material having numerousinterconnected air cells and at least one wall of the chamber is formedof a thin membrane of elastic gum.

The thin membrane constitutes at least a part of the upper surface ofthe sole or insole of the shoe thus defining a chamber having aresilient, collapsible wall. The air chamber is provided with a valvedinlet opening and an air intake passage extends from the inlet openingto the top edge of the upper. It is one of the features of thisinvention to form the portion of this air intake passage which traversesthe upper in the seam in the back cover of the sole and heel. The airchamber is also provided with a valve controlled discharge opening whichopens into the interior of the shoe preferably in the region of the toe,to insure thorough ventilation of all parts of the shoe as the forcedair moves back from this region to escape about the ankle.

The aforementioned and other objects and features of the invention willbe made fully apparent to those skilled in the art from a considerationof the following detailed description taken in conjunction with theaccompanying drawings in which:

FIG. 1 shows a longitudinal section through a shoe embodying a preferredform of the invention.

FIG. 2 shows a top plan view of the sole of the she shown in FIG. 1.

FIG. 3 i a fragmentary section taken on the line 33 of FIG. 1.

FIG. 4 is a detail showing on an enlarged scale the circled portion 4 ofFIG. 1.

FIG. 5 shows a section on the line 5-5 of FIG. 1 being on an enlargedscale and inverted for convenience in explanation.

FIG. 6 is a detail on an enlarged scale and inverted of the enclosedportion 6 of FIG. 1.

FIG. 7 shows on an enlarged scale a plan view of a valve used in thepresent invention.

FIG. 8 is a section taken on the line 88 of FIG. 7.

FIG. 9 shows a longitudinal section through a portion of a shoeembodying a modified form of the invention.

In the drawings, reference numeral 10 indicates generally the upper of arubber shoe having a sole 11 and an insole 12. An air chamber 13, whichcomprises a body of sponge rubber 14 and a covering membrane 15 is setin the fore part of the sole in a position to be engaged by that portionof the foot anterior to the arch so that it receives the weight of thewearer at each step in walking. Air is supplied to the chamber 13 by wayof air intake passages 16 which are positioned in the seam of the outercover at the back of the ankle and heel of the shoe. These passagesextend downwardly from the top edge of the cover to connect withpassages 17 formed between the sole 11 and the insole 12. The passages17 lead to inlet orifice 18 provided in the membrane 15. These orificesare normally closed by a valve 19 which opens in response to the suctionwithin chamber but which closes in response to pressure within thechamber to prevent a reverse flow of air through the passages 17 and 16.A discharge orifice 20 is provided in the membrane 15 at the forward endof the chamber 13 which orifice is controlled by a discharge valve 21arranged to permit the discharge of fresh air from the chamber into theinterior of the shoe and to prevent the reverse flow of air from theshoe to the chamber. It will be evident that whenever the air chamber 13is pressed the air contained in the sponge rubber within the chamber isforcedthrough the outlet orifice 20 into the toe part of the shoe, andthat as the pressure is relieved, the air chamber expands due to theelasticity of the sponge rubber 14, thereby sucking in fresh outer airthrough the passages 16 and 17. The valves 19 and 21 prevent the reverseflow of air regardless of the manner in which pressure is applied to themembrane. It will be understood that the valves 19 and 21 could beomitted since in the normal movement of walking, the right and left feetalternately come up and down each foot stepping down on the ground,touching it with the heel and then with the toe. In this normal walkingmovement the sole is pressed down from the heel to the toe and the airin the air chamber 13 is naturally pressed out toward the outlet orifice20, the inlet orifice 18 (FIG. 1) being more or less obstructed at thistime. As the rolling action of the foot is completed, the pressure isapplied in the area of the discharge or outlet orifice thus tending toobstruct air flow back through this orifice while the pressure to therear of the air chamber is relieved thus tending to draw air through theinlet orifice. Thus a portion of the objects of invention may beattained by resort to the valves 19 and 21. However, it is preferred touse these in order to assure that there will be no reverse flow of airunder any condition and in view of the ease with which such valves maybe supplied, as will hereinafter be set forth, this added assurance iswell worth the slight additional expense.

In the manufacture of the shoe so far described, the air intake passages16 maybe easily formed in the usual seam at the rear of the upper, inthe position shown in FIG. 3, by inserting vulcanized elastics coatedwith materials which prevent sticking in the seam between the overlappededges of the outer cover before the vulcanization of the shoe andthereafter pulling them out. The upper ends of the air intake passagesare thus positioned at the Patented Oct. 30, 1962 top of the shoe wherethere is little chance that moisture or dirt may be drawn in. Thisfavorable positioning of the air intake is further enhanced by theprovision of a cover 22 over the upper ends of the passages 16. Thecover is in the form of an inverted U. The legs of the U being fixed tothe inner and outer sides of the seam and the middle or curved partforming a semicircular shield over the upper ends of the passages 16. Asseen in FIG. 4 the curved portion of the cover is provided with inwardlyprojecting bristles 23 so that air may pass through the central portionof the curved part to the intake passages 16 while the entrance of dirtor water is inhibited. In view of this protection there is littlelikelihood that either of the passages 16 may become clogged, howeverthe provision of two passages 16 assures a supply of air to the chamber13 even if one of the passages should become obstructed.

The passages 16 lead to the passages 17 in the sole of the shoe. Thesepassages are easily provided by forming grooves in the underside of theinsole 12. In manufacturing, the insole is placed upside down as shownin FIG. 5 so that the underside thereof having the previously formedgrooves faces upwardly. The sole 11 is laid on the insole with the edgesof the upper inserted on all sides between them, care being taken thatthe passages 16 register with the passages 17.

The air chamber 13 is formed by providing a rectangular hole in theforward part of the insole 12. The rear side of this hole is formed of aslanting cut 25 and the membrane 15 is cemented or otherwise secured tothe surface of the slant and to the other sides of the hole in a mannerto fully close the same. The membrane 15 is of thin gum rubber orsimilar flexible, impervious sheet material, and capable of beingreadily expanded by the body of sponge rubber 14. The sole 11 is alsoprovided with a slanting cut 26 registering with and continuing theslanting surface provided by the cut so that when the two soles arejoined together a single slanting surface is provided within which liesthe inlet orifice 18. The body of foam rubber does not extend into thearea adjacent the inlet so that a free space 27 is provided in thisportion of the chamber permitting the valve 19 to open withoutobstruction. -It will be seen that when the sole 11 is cemented orsimilarly secured to the insole, the closure of the air chamber 13 andof the passages 17 becomes complete so that an air tight structure isprovided save for the intended inlet and discharge outlets.

The inlet and discharge valves 19 and 21 are simple and inexpensive inconstruction yet effective in operation. This construction isillustrated in detail in FIGS. 7 and 8, and it will be understood thatthough the valve there shown is applied to the discharge orifice 20 thesame structure may constitute the intake valve. The valve 21 consists ofa small square or rectangular piece of thin elastic sheet material, suchas latex or gum rubber, and which is positioned over the orifice 20being secured to the membrane 15 along two opposite edges as indicatedby the shaded areas 28. Preferably, the small square of gum has athickness of less than 0.1 millimeter. When air is forced through theorifice 20, the valve being very thin, expands and is raised up. Thusthe air can escape from the unstuck sides, while the valve completelyprevents the flow of air in the reverse direction.

The shoe described so far in conjunction with FIGS. l8 ilustrates apractical instance in which an air chamber is set in the front part ofthe sole. It will be understood that the air chamber may be otherwisepositioned, or that the entire insole may constitute such a chamber.Such a construction is illustrated in FIG. 9 in which an upper,indicated generally at 30, is provided with a sole 31 and an insole 32.The insole 32 consists of a body of sponge rubber 33, or equivalentmaterial having an airtight covering 34 of imperforate sheet material.The covering 34 is preferably made with comparatively thick rubberplates for the upper and lower surfaces thereof and the sides with thinelastic membrane so that the insole may expand up and down but berelatively stiff, or resistant to deformations within its surface area.The body of sponge rubber 33 maintains the insole 32 in an expandedstate in the absence of pressure thereon and thus constitutes acollapsible and expansible air chamber. Air is supplied to this chamberby way of air intake passages 35 which correspond to the inlet passages16 in the previously described form and which are protected in the sameway. The passages 35 extend by way of passage 36 in the heel and valve37 to a chamber 38 which is in continuous communication with theinterior of the sole by way of an opening 39. A discharge opening 40having a valve 41 is provided in toe portion of the insole to permit thedischarge of air from the chamber defined by the sole to the interior ofthe shoe. The valve 41 is structurally the same as that previouslydescribed in conjunction with FIGS. 7 and 8. The same may be said forthe valve 37 save for the fact that it is applied to a relatively rigidbase material rather than sheet material. The operation of the form ofthe invention disclosed in conjunction with FIG. 9 will be apparent fromthat of the form previously described.

It will be apparent that, with slight modifications, the form of theinvention disclosed in conjunction with FIG. 9 may be applied toordinary ready-made shoes and that it may be manufactured and sold as aseparate insole for use in such shoes. In such case, the intake passage35 could take the form of a fine rubber tube directly connected with theinterior of the insole by way of a suitable valve, for example a valvepositioned within the air chamber defined by the insole in the manneranalogous to that disclosed in FIG. 6.

From the preceding description, it will be evident that when theventilated rubber shoe of this invention is used, outer fresh air issupplied at each step to the interior of the shoe in the region of thetoe, and the air in the shoe is constantly refreshed and kept clean.When ordinary rubber shoes are worn for a long time during evenmoderately warm weather, the feet feel sweltery due to the fact that theair in the limited space between the foot and the cover soon becomessaturated with moisture since rubber lacks porosity and the power toabsorb. Heat is not dissipated and the resulting unwholesome conditionin the shoe tends to promote Water eczema and other skin diseases. Inthe winter such shoes are likewise uncomfortable since the moisturesaturated air is soon chilled and causes a cold, moist feeling in thefoot. The present invention obviates all of the disadvantages of suchshoes that are due to the lack of porosity or permeability whileretaining the obvious advantages of excluding the external moisture.

'It will, of course, be understood that various changes may be made inthe form, detail, arrangements and proportions of the various partsthroughout the views without departing from the scope of my invention.

It will thus be seen that there is provided a shoe in which the severalobjects of this invention are achieved, and which is well adapted tomeet the conditions of practical use.

As various possible embodiments might be made of the above invention,and as various changes might be made in the embodiments above set forth,it is to be understood that all matter herein set forth or shown in theaccompanying drawing is to be interpreted as illustrative and not in alimiting sense.

I claim:

A ventilated rubber shoe including an upper and a sole, an inner solecomprising a fiat body of porous elastic material covered by thin sheetmaterial thereby pro viding an air-tight chamber normally maintained inits expanded condition by said porous elastic material, means to supplyair to said chamber from a point adjacent the top edge of said upper atthe heel portion of said shoe, said means including an inlet passageformed in a seam 6 of said upper, a heel having an air inlet chamberthere- Ward end thereof, and a valve controlling said discharge inconnected with said inlet passage, an inlet valve in said opening. inletchamber controlling the admission of air from said inlet passage, saidthin sheet material of said insole hav- R ferences Cited in the file ofthis patent ing an opening communicating with said inlet chamber, 5UNITED STATES PATENTS said insole constituting an upper Wall of saidinlet chamber and closing the same except for the outlet provided 1lgcEwen et a1 171 by said opening in said thin sheet material of saidinsole, endmn said thin sheet material of said insole having a discharge3 opening in the upper surface thereof adjacent the for- 10

